COLL 1 |
| The challenge of the 21st Century is to produce catalysts that are capable of 100% selectivity for the desired reactions, often called “green chemistry”. This provides us with means to produce chemicals and fuels without byproducts and waste. The molecular ingredients of catalytic selectivity of metals include the control of surface structure, the mobility of adsorbates on the catalytically active surface, oxide-metal interface sites, selective site blocking, and the presence of hydrogen. Metal nanoparticles are produced by lithographic techniques as well as by colloid science techniques in solutions in the range of 1-12 nm in size with the desired surface structures. These nanoparticle arrays are supported on 2-dimensional oxide supports or encapsulated in 3-dimensional mesoporous high surface area oxides, and their catalytic selectivities for hydrocarbon conversion reactions and partial oxidation reactions are being explored. Techniques of characterization are different for 2-dimensional and 3-dimensional nanoparticle catalysts, and these will also be described in the lecture. The polymer capping over these growing metal nanoparticles protect them from aggregation but does not prevent the carrying out of high selectivity catalyzed reactions in solution. Experiments to monitor the rates and the selectivity of heterogeneous nanoparticles enzyme catalysts and homogeneous catalysts can be carried out under the same conditions in solution near room temperature. This approach carries the promise to develop a unified picture and molecular understanding of enzyme, homogeneous and heterogeneous catalysis. The molecular ingredients of mobility and surface structure sensitivity of the various catalytically selective systems will be reviewed and described. |
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Surface Chemistry Symposium in Honor of Gabor Somorjai
8:30 AM-12:00 PM, Sunday, 10 September 2006 Sir Francis Drake -- Franciscan Room, Oral
Division of Colloid & Surface Chemistry |